Sustainable Production of Bioactive Compounds From Persea indica

In this work we have investigated the accumulation of ryanoids in different plant parts (leaves, stems roots) of aeroponically grown Persea indica cloned trees (one year old cloned individuals) and a selected mature wild tree. We have tested the insect antifeedant (against Spodoptera littoralis, Myzus persicae and Rhopalosiphum padi) and nematicidal (against Meloidogyne javanica) effects of ethanolic extracts from these different plant parts. The HPLC-MS analysis of P. indica extracts showed that the mature tree (wild) leaves had 2 times more chemical diversity than the stems. The aeroponic plants showed lower differences in chemical diversity between leaves and stems, with the lowest diversity found in the roots. The ryanodane epiryanodol (1) was present in all the plant parts, with the mature stems (wild) having the highest amount. The aeroponic stems also accumulated ryanoids including 1, cinnzeylanol 2 and cinnzeylanone 4. The insect Spodoptera littoralis was strongly affected by the stem extracts while the leaf ones were moderately active. Based on the predicted vs. the real antifeedant values we conclude that the ryanoid content (1 or a combination of 2, 4 and 1) explained the antifeedant effects of the stem extracts while addition-al components contributed to the activity of the leaf ones. Therefore, careful individual selection of P. indica seedlings should be carried out prior to proceed with its aeroponic cultivation in or-der to obtain ryanodane-rich stem or leaf extracts with strong antifeedant effects on S. littoralis.

Morphological evaluation and determination keys of 21 citrus genotypes at seedling stage

Budiarto R, Poerwanto R, Santosa E, Efendi D. 2021. Morphological evaluation and determination keys of 21 citrus genotypes at seedling stage. Biodiversitas 22: 1570-1579. The identification of citrus varieties is generally based on flower, fruit, and mature tree characters. The detailed and comprehensive identification of seedling stage is very limited, therefore present study aimed to identify and distinguish 21 citrus genotypes based on 50 morphological characters of vegetative shoot at seedling stage. Cluster analysis using complete linkage agglomerative method showed broader dissimilarities between C. x limon and C. x microcarpa. Unfortunately, this method was limited to differentiate six genotypes within Citrus reticulata Blanco due to extremely low dissimilarities found. All citrus seedlings have similarities in the forms of habitus, gland spots, arrangement and venation of leaf. The result of PCA determined petiole wing, spine, color, hair and fragrance of leaves as five morphological markers at seedling stage. In addition, there was a positive correlation between spine and leaf pleasant. Moreover, the details of morphological dissimilarities between genotypes were described in arranged determination keys.

Influence of the Tree Decay Duration on Mechanical Stability of Norway Spruce Wood (Picea abies (L.) Karst.)

Wood properties have an influence on the safety around the tree itself as well as on actual possibilities of using wood. The article focuses on the wood properties of the Norway spruce (Picea abies (L.) Karst.) in reference to the time since the tree has decayed. The study was conducted among mature tree stands of spruce in Białowieża Forest, where over the last 10 years there has been a weakening of spruce tree stands due to water deficiency which has contributed to the gradation of the European spruce bark beetle (Ips typographus). The study focused on spruce wood of living and healthy specimens as well as the wood of standing trees which has decayed between one and five years before the sample was collected. The findings indicate a gradual decrease in wood properties as time passed since the physiological decay of the tree. Significant differences in the decrease of mechanical wood properties have been observed in trees which had been decayed for 3 years and they should be considered life and health hazard for people and animals.

Vegetative propagation of Afzelia africana Sm. Ex Pers.: a multipurpose and threatened tree

Afzelia africana is at the verge of extinction from continuous exploitation without replacement, thus propagation of this tree species is expedient. Vegetative propagation is a reliable means of propagation of tree species. This study therefore describes a protocol for the vegetative propagation of Afzelia africana by using stem cuttings from its mature tree (20 years old) and saplings (2 years old). Herbaceous (non - lignified portion of the stem) and semi – hard wood cuttings (lignified portion of the stem) (with and without leaves) were treated with high and low concentrations of Indole butyric acid (IBA) solution via the quick dip and the soaking method of application and planted on forest soil and river sand in a humidifier. Cuttings from mature tree planted on forest soil and river sand did not respond to any treatment. Also, no response was observed on cuttings collected from saplings and planted on forest soil; however, cuttings planted on river sand sprouted. The presence and absence of leaves and IBA treatment had an interaction effect on root number (0.02) and root length (0.0001). The response from herbaceous cuttings was significantly higher than from semi – hard wood cuttings with respect to root number (1.00) and root length (5.82 cm). Cutting type and IBA treatment also had an interaction effect on root number (0.05) and root length (0.0007). Herbaceous leafy stem cuttings of A. africana treated with 400 ppm IBA and planted on river sand is suitable for rooting stem cuttings of A. africana for raising seedlings for reforestation, afforestation and other conservation purposes. © 2020 International Formulae Group. All rights reserved. Keywords: Rooting, cuttings, Afzelia africana, hormone, humidifier

POPULATION DISTRIBUTION AND DIVERSITY OF Pycnanthus angolensis IN RAINFOREST SOUTHWEST, NIGERIA

Population distributionof Pycnanthus. angolensis was carried out in two locations of three States (Osun, Ekiti and Oyo) due to abundance and availability using direct enumeration. A total of 58 stands of plant viz Osun state 58.93%, Ekiti State 28.57% and Oyo State 12.50% were assessed. Variation occurred within each State (Osun State: Ila 32.35% >20.59% Olooyo and Mojapa, Gbongan 17.65%, Ile Ogbo 5.88% and least in Ajaba (2.94%). In Ekiti State, Osan 43.75% > Otun 31.25%. > 25% Ayetoro Ekiti. In Oyo State, Adewumi, 28.57% > 14.29 %> Idito, Erumu, Sapara (U.I), Mosque (U.I) and Amina (U.I), 39 juvenile and 19 mature trees (flowering and fruiting) varied in ratios 30:6 Osun State, 9:7 Ekiti State and 0:6 Oyo state respectively. Osun State had the highest number of juvenile trees (30), 9 in Ekiti State and zero juvenile in Oyo state. Ekiti State had the highest number of mature tree 7> Oyo and Osun (6). Osun State had greater number of juvenile trees than Ekiti and Oyo States. P. angolensis was found growing in fallow or abandoned land, marshy areas, farmland, river side, new site areas and Quarters. P. angolensis could be found on different habitats among the States and within the States. Given the high rate of forest destruction in the country, there is need to ensure sustainable conservation of the forest area to avoid further destruction by provision of alternative means of livelihood for the local population so as to reduce their dependence on these forest.